Use of compounds for the regulation of food intake

ABSTRACT

Compounds that are ligands for the growth hormone secretagogue receptor type 1A (GHS-R 1A), as well as pharmaceutically acceptable salts of such compounds, are useful for the manufacture of medicaments for the regulation of food intake.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation of application Ser. No.09/771,770 filed on Jan. 29, 2001 and claims priority under 35 U.S.C.119 of Danish application no. PA 2000 00161 filed Feb. 1, 2000 andDanish application no. PA 2000 01107 filed Jul. 17, 2000, the contentsof which are fully incorporated herein by reference.

[0002] Priority of U.S. provisional application No. 60/181,303 filedFeb. 9, 2000 is claimed under 35 U.S.C. 119.

FIELD OF THE INVENTION

[0003] The present invention relates to the use of a compound that is aligand for the growth hormone secretagogue receptor type 1A (GHS-R 1A)for the regulation of food intake or food intake. The present inventionalso embraces pharmaceutical compositions comprising these compounds andmethods of using the compounds and their pharmaceutical compositions.

BACKGROUND OF THE INVENTION

[0004] Stimulation of food intake is important in connection withpatients suffering from anorexia due to chronic medical conditions,eating disorders, and other conditions in which excessive weight losshas produced a detrimental effect on the patients' health.

[0005] In other situations, suppression of food intake is important.Obesity is a well-known risk factor for the development of many verycommon diseases such as atherosclerosis, hypertension, Type II diabetes(non-insulin dependent diabetes mellitus (NIDDM)), dyslipidemia,coronary heart disease, and osteoarthritis and various malignancies. Italso causes considerable problems through reduced mobility and decreasedquality of life. The incidence of obesity and thereby also thesediseases is increasing throughout the entire industrialized world.Except for exercise, diet and food restriction, no convincing treatmentfor reducing body weight effectively and acceptably currently exist.However, due to the important effect of obesity as a risk factor inserious and even fatal and common diseases, it will be important to findpharmaceutical compounds useful in prevention and treatment of obesity.

[0006] Even mild obesity increases the risk of premature death,diabetes, hypertension, atherosclerosis, gallbladder disease and certaintypes of cancer. In the industrialized western world the prevalence ofobesity has increased significantly in the past few decades. Because ofthe high prevalence of obesity and its health consequences, itsprevention and treatment should be a high public health priority.

[0007] When energy intake exceeds energy expenditure, the excesscalories are stored in adipose tissue, and if this net positive balanceis prolonged, obesity results, i.e., there are two components to weightbalance, and an abnormality on either side (intake or expenditure) canlead to obesity.

SUMMARY OF THE INVENTION

[0008] The present invention relates, inter alia, to the use of acompound that is a ligand for the receptor GHS-R 1A, or pharmaceuticallyacceptable salts thereof, for the manufacture of a medicament for theregulation of food intake.

DESCRIPTION OF THE INVENTION

[0009] Accordingly, the present invention provides the use of a compoundthat is a ligand for the receptor GHS-R 1A, or pharmaceuticallyacceptable salts thereof, for the manufacture of a medicament for theregulation of food intake.

[0010] A further aspect of the present invention relates to a method forthe regulation of food intake, which method comprises administering aneffective amount of a compound that is a ligand for the receptor GHS-R1A, or pharmaceutically acceptable salts thereof, to a patient in needof such a treatment.

[0011] A still further aspect of the present invention relates to theuse of a compound that is a ligand for the receptor GHS-R 1A, orpharmaceutically acceptable salts thereof, for the manufacture of amedicament for the regulation of Body Mass Index (BMI).

[0012] A further aspect of the present invention relates to the use of acompound that is a ligand for the receptor GHS-R 1A, or pharmaceuticallyacceptable salts thereof, for the manufacture of a medicament for thetreatment of anorexia.

[0013] A still further aspect of the present invention relates to theuse of a compound that is a ligand for the receptor GHS-R 1A, orpharmaceutically acceptable salts thereof, for the manufacture of amedicament for the treatment of lack of appetite in children with agrowth hormone deficiency.

[0014] A further aspect of the present invention relates to the use of acompound that is a ligand for the receptor GHS-R 1A, or pharmaceuticallyacceptable salts thereof, for the manufacture of a medicament for thetreatment of obesity.

[0015] A still further aspect of the present invention relates to theuse of a compound that is a ligand for the receptor GHS-R 1A, orpharmaceutically acceptable salts thereof, for the manufacture of amedicament for the treatment of Type II diabetes.

[0016] A further aspect of the present invention relates to the use of acompound that is a ligand for the receptor GHS-R 1A, or pharmaceuticallyacceptable salts thereof, for the manufacture of a medicament for thetreatment of wasting associated with various diseases or conditions,e.g., wasting associated with AIDS, chronic liver disease, chronicobstructive pulmonary disease (COPD) or respiratory insufficiency ingeneral, as well as wasting associated with bone fractures or withageing. Wasting, which involves a progressive loss of body mass,including muscle mass, is normally attributable to a catabolic state ofmetabolism, and is frequently difficult to reverse by purely dietarymeans.

[0017] In one embodiment of the present invention the receptor GHS-R 1Ais the human GHS-R 1A receptor. In another embodiment the medicament isfor humans.

[0018] In a still further embodiment of the invention the compound doesnot induce a therapeutically effective growth hormone release at thetherapeutic dose of the compound.

[0019] In a further embodiment of the invention the medicament is anon-injectable medicament. In a still further embodiment the medicamentis an oral medicament.

[0020] The receptor GHS-R 1A (the growth hormone secretagogue receptortype 1A) is described by Howard, A. D. et al. (1996) in Science 273,974-977.

[0021] The binding of a compound to the receptor GHS-R 1A can, e.g., bemeasured by the use of the assays as described in Example 1 herein.

[0022] In one embodiment of the invention the ligand has a potency(EC₅₀) on the GHS-R 1A of less than 500 nM. In another embodiment theligand has a potency (EC₅₀) on the GHS-R 1A of less than 100 nM.

[0023] In a further embodiment the binding constant (K_(D)) of theligand is less than 500 nM. In a still further embodiment the bindingconstant (K_(D)) of the ligand is less than 100 nM.

[0024] In yet another embodiment of the invention the ligand is anagonist for the receptor GHS-R 1A. In another embodiment of theinvention the ligand is an antagonist for the receptor GHS-R 1A.

[0025] In a still further embodiment the compound employed in accordancewith the invention is adenosine. In a further embodiment the compound isghrelin or a peptide homologous thereto. Ghrelin, a peptide having thesequence GSSFLSPEHQRVQQRKESKKPPAKLQPR, is described by Kojima in Nature(1999), Vol. 402, 656-660.

[0026] Peptides homologous to ghrelin are peptides which have an aminoacid sequence which has a degree of identity to ghrelin of at leastabout 70%, preferably at least about 80%, more preferably at least about90%, even more preferably at least about 95%, and most preferably atleast about 97%, and which qualitatively retain the activity as a ligandfor the receptor GHS-R 1A. The degree of identity between two or moreamino acid sequences may be determined by means of computer programsknown in the art, such as GAP provided in the GCG program package(Needleman and Wunsch, 1970, Journal of Molecular Biology 48:443-453).For the purposes of determining the degree of identity between two aminoacid sequences for the present invention, GAP is used with the followingsettings: GAP creation penalty of 3.0 and GAP extension penalty of 0.1.

[0027] Within the context of the present invention, “a therapeuticallyeffective growth hormone release” is to be understood as a growthhormone release that would have a therapeutic effect in treatment of thespecific indication, e.g., regulation of food intake.

[0028] The therapeutic dose of the compound will depend upon thefrequency and mode of administration, the sex, age, weight and generalcondition of the subject treated, the nature and severity of thecondition treated and any concomitant diseases to be treated, and otherfactors evident to those skilled in the art. In one embodiment, theeffective amount of the compound is in the range from about 0.05 toabout 2000 mg, preferably from about 0, 1 mg to about 1000 mg, andespecially from about 0.5 to about 500 mg per day.

[0029] The term obesity implies an excess of adipose tissue. In thiscontext, obesity is best viewed as any degree of excess adiposity thatimparts a health risk. The distinction between normal and obeseindividuals can only be approximated, but the health risk imparted byobesity is probably a continuum with increasing adiposity. However, inthe context of the present invention, individuals with a Body Mass Index(BMI, defined as the body weight of a human individual in kilogramsdivided by the square of the height of that individual in meters) above25 are to be regarded as obese.

[0030] The present invention also encompasses pharmaceuticallyacceptable salts of the present compounds. Such salts includepharmaceutically acceptable acid addition salts, pharmaceuticallyacceptable metal salts, ammonium salts and alkylated ammonium salts.Acid addition salts include salts of inorganic acids as well as organicacids. Representative examples of suitable inorganic acids includehydrochloric, hydrobromic, hydriodic, phosphoric, sulpfuric and nitricacids and the like. Representative examples of suitable organic acidsinclude formic, acetic, trichloroacetic, trifluoroacetic, propionic,benzoic, cinnamic, citric, fumaric, glycolic, lactic, maleic, malic,malonic, mandelic, oxalic, picric, pyruvic, salicylic, succinic,methanesulfonic, ethanesulfonic, tartaric, ascorbic, pamoic,bismethylene salicylic, ethanedisulfonic, gluconic, citraconic,aspartic, stearic, palmitic, ethylenediaminetetraacetic (EDTA),p-aminobenzoic, glutamic, benzenesulfonic and p-toluenesulfonic acidsand the like. Further examples of pharmaceutically acceptable inorganicor organic acid addition salts include the pharmaceutically acceptablesalts listed in J. Pharm. Sci. 1977, 66, 2, which is incorporated hereinby reference. Examples of metal salts include lithium, sodium, potassiumand magnesium salts and the like. Examples of ammonium and alkylatedammonium salts include ammonium, methylammonium, dimethylammonium,trimethylammonium, ethylammonium, hydroxyethylammonium, diethylammonium,butylammonium and tetramethylammonium salts and the like.

[0031] Also included within the scope of compounds or pharmaceuticallyacceptable acid addition salts thereof in the context of the presentinvention are any hydrates (hydrated forms) thereof.

[0032] Within the context of the present invention, a “ligand for thereceptor GHS-R 1A” is understood to refer to any compound that hasaffinity to the receptor GHS-R 1A as measured by the method as describedin Example 1 herein.

[0033] Within the context of the present invention, treatment is to beunderstood as treatment and/or prevention.

[0034] In a still further aspect, the invention relates to apharmaceutical composition comprising, as an active ingredient, acompound as defined above or a pharmaceutically acceptable salt thereoftogether with a pharmaceutically acceptable carrier.

[0035] In a further aspect of the invention the present compounds may beadministered in combination with further pharmacologically activesubstances, e.g., an antidiabetic agent or other pharmacologicallyactive material, including other compounds for the treatment and/orprevention of insulin resistance and diseases wherein insulin resistanceis the pathophysiological mechanism.

[0036] Furthermore, the compounds according to the invention may beadministered in combination with antiobesity agents or foodintake-regulating agents.

[0037] A still further aspect of the present invention is a method ofidentifying candidate compounds that regulate food intake, characterizedby screening out compounds that act as ligands for the receptor GHS-R1A. This method for identifying candidate compounds comprises:

[0038] (a) contacting a growth hormone secretagogue receptor type 1A(GHS-R 1A), or a fragment thereof having GHS-R 1A ligand-bindingactivity, in the presence of increasing amounts of a compound ofinterest not known to have GHS-R 1A ligand-binding activity;

[0039] (b) measuring the binding of the known GHS-R 1A ligand to theGHS-R 1A receptor; and

[0040] (c) determining the concentration of the compound of interest atwhich the binding of said ligand to said receptor is reduced to 50% ofbinding in the absence of said compound,

[0041] wherein, if said concentration is about 500 nm or less, thecompound is a candidate compound that regulates food intake.

[0042] A further aspect of the present invention relates to a compoundidentified by or identifiable by this method.

[0043] Pharmaceutical Composition

[0044] The compounds of the invention may be administered alone or incombination with pharmaceutically acceptable carriers or excipients, ineither single or multiple doses. The pharmaceutical compositionsaccording to the invention may be formulated with pharmaceuticallyacceptable carriers or diluents as well as any other known adjuvants andexcipients in accordance with conventional techniques such as thosedisclosed in Remington: The Science and Practice of Pharmacy, 19^(th)Edition, Gennaro, Ed., Mack Publishing Co., Easton, Pa., 1995.

[0045] The pharmaceutical compositions may be specifically formulatedfor administration by any suitable route such as the oral, rectal,nasal, pulmonary, topical (including buccal and sublingual),transdermal, intracisternal, intraperitoneal, vaginal and parenteral(including subcutaneous, intramuscular, intrathecal, intravenous andintradermal) route, the oral route being preferred. It will beappreciated that the choice of route will depend on the generalcondition and age of the subject to be treated, the nature of thecondition to be treated and the active ingredient chosen.

[0046] Pharmaceutical compositions for oral administration include soliddosage forms such as capsules, tablets, dragees, pills, lozenges,powders and granules. Where appropriate, they can be prepared withcoatings, such as enteric coatings, or they can be formulated so as toprovide controlled release of the active ingredient, such as sustainedor prolonged release according to methods well known in the art.

[0047] Liquid dosage forms for oral administration include solutions,emulsions, suspensions, syrups and elixirs.

[0048] Pharmaceutical compositions for parenteral administration includesterile aqueous and non-aqueous injectable solutions, dispersions,suspensions or emulsions, as well as sterile powders to be reconstitutedin sterile injectable solutions or dispersions prior to use. Depotinjectable formulations are also contemplated as being within the scopeof the present invention.

[0049] Other suitable administration forms include suppositories,sprays, ointments, creams, gels, inhalants, dermal patches, implants,etc.

[0050] A typical oral dosage of a compound employed according to theinvention is in the range of from about 0.0001 to about 100 mg/kg bodyweight per day, preferably from about 0.001 to about 10 mg/kg bodyweight per day, and more preferably from about 0.01 to about 1 mg/kgbody weight per day, administered in one or more doses, such as 1 to 3doses.

[0051] The formulations may conveniently be presented in unit dosageform by methods known to those skilled in the art. A typical unit dosageform for oral administration one or more times per day, such as 1 to 3times per day, may contain from about 0.05 to about 2000 mg, preferablyfrom about 0.1 to about 500 mg, and more preferably from about 0.5 mg toabout 200 mg of a compound employed according to the invention.

[0052] For parenteral routes, such as intravenous, intrathecal,intramuscular and similar routes of administration, doses are typicallyof the order of about half the dose employed for oral administration.

[0053] The compounds of this invention are generally utilized as thefree substance or as a pharmaceutically acceptable salt thereof. Oneexample is an acid addition salt of a compound having a free basefunctionality. When a compound of the invention contains a free basefunctionality, such salts are suitably prepared in a conventional mannerby treating a solution or suspension of the free base form of thecompound with, typically, one equivalent (chemical equivalent, i.e.acid-base equivalent) of a pharmaceutically acceptable acid, for examplean inorganic or organic acid chosen among the representative examplesthereof mentioned above. Physiologically acceptable salts of a compoundwith a hydroxy group include the anion of said compound in combinationwith a suitable cation, such as sodium or ammonium ion.

[0054] For parenteral administration, solutions of the present compoundsin sterile aqueous solution, aqueous propylene glycol or sesame orpeanut oil may be employed. Such aqueous solutions should be suitablybuffered if necessary, and the liquid diluent first rendered isotonicwith sufficient saline or glucose. The aqueous solutions areparticularly suitable for intravenous, intramuscular, subcutaneous andintraperitoneal administration. The sterile aqueous media employed areall readily available by standard techniques known to those skilled inthe art.

[0055] Suitable pharmaceutical carriers include inert solid diluents orfillers, sterile aqueous solution and various organic solvents. Examplesof solid carriers are lactose, terra alba, sucrose, cyclodextrin, talc,gelatin, agar, pectin, acacia, magnesium stearate, stearic acid or loweralkyl ethers of cellulose. Examples of liquid carriers are syrup, peanutoil, olive oil, phospholipids, fatty acids, fatty acid amines,polyoxyethylene or water. Similarly, the carrier or diluent may includeany sustained-release material known in the art, such as glycerylmonostearate or glyceryl distearate, alone or mixed with a wax. Thepharmaceutical compositions formed by combining the compounds of theinvention and the pharmaceutically acceptable carriers are then readilyadministered in a variety of dosage forms suitable for the disclosedroutes of administration. The formulations may conveniently be presentedin unit dosage form by methods known in the art of pharmacy.

[0056] Formulations of the present invention suitable for oraladministration may be presented as discrete units such as capsules ortablets, each containing a predetermined amount of the activeingredient, and which may include a suitable excipient. Theseformulations may be in the form of powder or granules, as a solution orsuspension in an aqueous or non-aqueous liquid, or as an oil-in-water orwater-in-oil liquid emulsion.

[0057] If a solid carrier is used for oral administration, thepreparation may be tabletted, placed in a hard gelatin capsule in powderor pellet form, or it can be in the form of a troche or lozenge. Theamount of solid carrier will vary widely, but will usually be from about25 mg to about 1 g. If a liquid carrier is used, the preparation may bein the form of a syrup, emulsion, soft gelatin capsule or sterileinjectable liquid, such as an aqueous or non-aqueous liquid suspensionor solution.

[0058] A typical tablet that may be prepared by conventional tablettingtechniques may contain: Core: Active compound (as free compound or saltthereof) 5 mg Colloidal silicon dioxide (Aerosil ™) 1.5 mg Cellulose,microcryst. (Avicel ™) 70 mg Modified cellulose gum (Ac-Di-Sol ™) 7.5 mgMagnesium stearate q.s. Coating: Hydroxypropylmethylcellulose (HPMC)approx. 9 mg *Mywacett ™ 9-40 T approx. 0.9 mg

[0059] The compounds of the invention may be administered to a mammal,especially a human, in need thereof. Such mammals include also animals,both domestic animals, e.g., household pets, and non-domestic animalssuch as wildlife.

[0060] If desired, the pharmaceutical composition of the invention maycomprise the compound of the invention in combination with furtherpharmacologically active substances such as those described in theforegoing.

[0061] The present invention is further illustrated by the followingexamples which, however, are not to be construed as limiting the scopeof protection.

EXAMPLES Example 1

[0062] Identification of Ligands for the Receptor GHS-R 1A

[0063] Transfection

[0064] Lipofectamine (Life Technologies, Rockville, Md., U.S.A.) wasused for transfection of BHK cells with a GHS-R 1A expression vector(Howard, A. D. et al. (1996), Science 273, 974-977).

[0065] Receptor Binding Assay

[0066] Receptor binding was assayed as described in Hansen, B. S. et al(1999) Eur.J.Endocrinol. 141:180-189. Briefly, crude membranes fromstably transfected BHK/GHS-R 1A cells were suspended at 0.5 mgprotein/ml in homogenization buffer (25 mM Tris-base, 2.5 mM EDTA, 10 mMMgCl₂ and 30 μg/ml bacitracin). In a microtiter plate 10 μl membranesuspension was combined with either ³⁵S-labelled MK0677 (see Example 4)(Amersham Pharmacia Biotech, Essex, UK) or 2- ³H-adenosine (Amersham) aswell as binding buffer (2.5 mM Tris-base, 2.5 mM EDTA and 10 mM MgCl₂)to a total volume of 250 μl. Non-specific binding was determined byadding 10 μM MK0677 (see Example 4) or 10 μM adenosine to the assay. Theassay was subsequently incubated at 30° C. for 60 minutes, followed byapplication of the samples to GF/B filters (Whatman, Kent, UK) which hadbeen pre-treated with 0.5% polyethylenimine for 60 minutes. The filterswere subsequently washed in 0.9% NaCl and counted using an Optiphase™‘HiSafe 3’ counter (Wallac, Turku, Finland).

[0067] To test for compounds that can compete with binding of either³⁵S-MK0677 or ³H-adenosine to the GHS-R 1A, different concentrations(0.001 nmol/l to 10 μmol/l) of the compound were added to the incubationdescribed above.

[0068] Specific binding was determined as the difference between totalbinding and non-specific binding (binding in the presence of 10 μMunlabelled ligand). Binding curves were generated using either thenon-linear regression or hyperbolic fit feature of the GraphPad™ Prismsoftware package (GraphPad, San Diego, Calif., U.S.A.).

[0069] Calcium Imaging

[0070] To test for agonism or antagonism of the compounds that cancompete with the binding of the radiolabelled ligands in the abovereceptor assay, a functional assay based on stimulation of the releaseof Ca⁺⁺ via the GHS-R was developed.

[0071] GHSR-expressing cells were cultured in Lab-Tek™ chamberedcoverglasses (Nalge Nunc Int., Naperville, Ill., USA). Prior to theexperiment, cells were loaded with the Ca²⁺-sensitive dye, Fura2-AM(Molecular Probes Inc., Eugene, Oreg., U.S.A.), according to standardprocedures. The chambers were placed on a temperature-regulatedmicroscope stage and kept at 37° C. Fluorescence images were acquiredusing the MetaFluor™ software package (Universal Imaging Corporation,West Chester, Pa., U.S.A.) together with a Zeiss Axiovert™ 100S invertedmicroscope (Carl Zeiss, Oberkochen, Germany) and a Princeton™MicroMAX-5-1300Y CCD camera (Princeton instruments, Trenton, N.J.,U.S.A.). The microscope was also equipped with a 530 nm±15 nm emissionfilter, a 500 nm dichroic mirror (Delta Lys & Optik, Lyngby, Denmark)and a filterwheel (LUDL electronic products, Hawthorne, N.Y., USA)harbouring 340 nm±10 nm and 380 nm±10 nm excitation filters (Delta Lys &Optik). Images were acquired every 3 seconds. After acquisition of 12-14images, the cells were stimulated with adenosine, MK0677 or othercompounds. To test for antagonism the compounds were added together witheither adenosine or MK0677. In each experiment the Fura2 ratio (ratiobetween the measured intensities of emission at 510 nm followingexcitation at 340 nm and at 380 nm, respectively) was followed in 50cells. A normalized ratio was generated for each cell by dividing theFura2 ratio at time t with the ratio at time zero. The data representedthe average normalized Fura2 ratio for 50 cells in a typical experiment.All experiments were repeated at least 4 times (giving similar results).

Example 2

[0072] Identification of Adenosine as a Ligand for the Receptor GHS-R 1A

[0073] The methods of example 1 were used. Adenosine was found to be apotent ligand for the GHS-R 1A (EC₅₀˜50 nM using the Ca⁺⁺ assaydescribed above). Binding studies were performed to characterize thebinding of adenosine to the GHS-R 1A, and a K_(D) of 87±10 nM wasdetermined.

[0074] Adenosine was, however, unable to stimulate GH secretion from ratpituitary cells (assay described e.g. in Hansen, B. S. et al (1999)Eur.J.Endocrinol. 141:180-189).

Example 3

[0075] Adenosine Does not Stimulate Growth Hormone Release, butStimulates Feeding

[0076] The effect on GH release was studied in Halothane anaesthetizedmale Wistar rats after intracerebroventricular (icv) and intravenous(iv) administration of adenosine and also in pentobarbital anaesthetizedcatheterized female Sprague Dawley (SD) rats after iv administration.Vehicle or adenosine was given to groups of rats (n=4-6) in thefollowing doses: 10 μg/rat and 100 μg/rat icv dissolved in 5 μl saline,1 mg/kg iv and also 10 mg/kg iv to the SD rats. Blood samples wereobtained from anaesthetized animals before dosing, and either 10 minafter dosing or by frequent blood sampling through a catheter up until45 min after dosing. The plasma was analyzed for rat GH.

[0077] The effect on feeding was studied in conscious non-deprived maleWistar rats (n=7-10) after icv dosing of vehicle or adenosine (1 μg/ratand 10 μg/rat in 5 μl saline). Food intake was measured in feeding boxeswith standard chow and water placed on balances connected to a computer.Changes in weight of chow and water were continuously registered. Foodand water intake were measured for 3 hours after drug injection duringearly daytime, when food intake is normally at a very low level.

[0078] The results showed that adenosine did not stimulate GH release inany of the given doses, neither by the icv nor the iv route ofadministration.

[0079] With respect to the orexigenic effect of adenosine, there was noeffect after 1 μg/rat, but food intake was significantly increasedcompared to the vehicle control group after injection of 10 μg/ratadenosine icv.

Example 4

[0080] Correlation Between GHS-R 1A Binding Affinity and the Effect onFood Intake

[0081] The compounds used were characterized by showing equipotency withrespect to in vitro GH release from primary rat somatotrophs, althoughthey displayed significantly different binding affinity to the GHS-R 1A.

[0082] The following compounds (structures shown below) were employed:NNC 26-1291, with a high binding affinity to the receptor similar tothat of MK0677 (K_(i)=0.4±0.06 nM), NNC 26-1187 with an intermediatebinding affinity (K_(i)=22.2±7 nM), and NN703 displaying a weak bindingaffinity (K_(i)=112±29 nM).

[0083] NN703 is described in WO 97/23508, and this compound, togetherwith MK0677 (the latter also being denoted MK677), is also described in,e.g., Drug Discovery Today, vol. 4, No. 11, November 1999, pp. 497-506.NNC 26-1291 and NNC 26-1187 are growth hormone secretagogues of anon-peptidyl nature and are described in WO 99/58501 and WO 00/26252,respectively.

[0084] The effect on feeding was tested after icv injections innon-deprived male Wistar rats. The compounds were dissolved in 5 μlsaline and injected in the following doses: 10.0 μg per rat (NNC26-1291) and 30.0 μg per rat (NN703 and NNC 26-1187).

[0085] Food intake was measured in feeding boxes, where standard chowand water were placed on balances and changes in weight continuouslyregistered. Food and water intake was measured for 3 hours after druginjection in the beginning of the light part of the diurnal cycle, whenfood intake is normally at a very low level. All three compoundsincreased food intake. The effect of NN703 was moderate, with a foodintake at about 3 grams, while NNC 26-1187 and particularly NNC 26-1291showed stronger effects with food intakes at about 4-5 grams. Forcomparison, food intake in control animals is normally about 1 gram, andicv administration of 10 μg porcine neuropeptide Y (NPY), which has astrong effect on food intake, increases food consumption to about 8grams in this model.

[0086] The compounds employed were as follows:

Example 5

[0087] Ghrelin Stimulates Feeding, but not GH Release, After icvAdministration

[0088] Non-deprived male Wistar rats (n=6-10) were used for the study,dosed with vehicle or with ghrelin at 10 μg/rat icv dissolved in 5 μlsaline. Food intake was measured in conscious animals, using feedingboxes. Food and water intake were measured for 3 hours after druginjection during early daytime, when food intake is normally at a verylow level. GH release was measured in Halothane-anaesthetized animalsfrom which blood samples were obtained, before dosing and 10 min afterdosing, via the orbital plexus. The plasma was analyzed for rat GH.

[0089] Ghrelin administered in this manner (icv administration) produceda significant effect on feeding, compared to vehicle, but did notstimulate GH release. In contrast, it is known that ghrelinadministration by the iv route causes stimulation of GH release.

1 1 1 28 PRT Homo sapiens 1 Gly Ser Ser Phe Leu Ser Pro Glu His Gln ArgVal Gln Gln Arg Lys 1 5 10 15 Glu Ser Lys Lys Pro Pro Ala Lys Leu GlnPro Arg 20 25

What is claimed is:
 1. A method for regulating food intake, comprising:administering to a subject in need thereof a compound that is an agonistfor the growth hormone secretagogue receptor type 1A (GHS-R 1A), or apharmaceutically acceptable salt thereof, in an amount effective toregulate such food intake.
 2. The method of claim 1, wherein thecompound does not induce a therapeutically effective growth hormonerelease at the effective dose of the compound.
 3. The method of claim 1,wherein the compound is grehlin or a homologue thereof.
 4. A method fortreating anorexia, comprising: administering to a subject in needthereof a compound that is an agonist for the growth hormonesecretagogue receptor type 1A (GHS-R 1A), or a pharmaceuticallyacceptable salt thereof, in an amount effective for such treatment.
 5. Amethod for treating the lack of appetite in a child with growth hormonedeficiency, comprising: administering to the child a compound that is anagonist for the growth hormone secretagogue receptor type 1A (GHS-R 1A),or a pharmaceutically acceptable salt thereof, in an amount effectivefor such treatment.
 6. A method for treating obesity, comprising:administering to a subject in need thereof a compound that is an agonistfor the growth hormone secretagogue receptor type 1A (GHS-R 1A), or apharmaceutically acceptable salt thereof, in an amount effective forsuch treatment.
 7. A method for treating Type II diabetes, comprising:administering to a subject in need thereof a compound that is an agonistfor the growth hormone secretagogue receptor type 1A (GHS-R 1A), or apharmaceutically acceptable salt thereof, in an amount effective forsuch treatment.
 8. A method for treating wasting associated with AIDS,comprising: administering to a subject in need thereof a compound thatis an agonist for the growth hormone secretagogue receptor type 1A(GHS-R 1A), or a pharmaceutically acceptable salt thereof, in an amounteffective for such treatment.